High fidelity, universal gates on a noise-decoupled, coherence enhanced flux-tunable transmon

Flux tunable superconducting qubits often have decay-limited coherence at flux sweet spots but may suffer from high pure-dephasing while they are flux biased away from that sweet spot. We present the results of our experiment, performing fast, high fidelity, universal single-qubit gates, on a noise-decoupled flux-tunable transmon qubit that is biased far away from its flux sweet spot. Under these conditions, the noise-decoupled transmon benefits from a factor of 10 enhancement of coherence. This technique can expand operational ranges of qubits, broadening the selection of viable qubit operational regimes by making qubits in otherwise low-coherence configurations operable with high coherence. The efficacy of this technique is not limited to the superconducting circuits.